The present invention relates to a cover layer preferably to be applied on the sample side of optical ion sensors, and to a method of preparing such a layer.
In clinical applications of analytical chemistry optical sensors have become increasingly important over the last few years; among other advantages, they are easier to miniaturize than conventional electrochemical sensors.
Optical sensors, so-called "optodes", essentially are transparent substrates on which indicators based on absorption dyes or fluorescent dyes are immobilized both chemically and physically.
The functional principle of such sensors is based on the specific interaction between the species to be analyzed and the indicator, and on the subsequent changes in the light-absorbing or fluorescent properties of the indicator--depending on the type of indicator used.